svn merge -r74200:76302 svn+ssh://svn.lindenlab.com/svn/linden/branches/Branch_1-18-6-Viewer --> release

Wheee, this was fun. Um, let's back-port fixes a little more rapidly next time. Reviewed by CG until alexandria died, did the rest by my lonesome.

Result of svn merge -r71162:71205 svn+ssh://svn/svn/linden/branches/new-license into release. only changes files which are not deployed or the comments section of code.

corrected, removed, and updated comments throughout the code to be more useful. no code changes. SL-13762